Poaceae (Gramineae)

The most economically important family of flowering plants ... oats rice wheat The most economically important family of flowering plants ... sugar cane bamboo

Ceres - the Roman goddess of agriculture

And the fourth largest: 600 Genera /10, 000 species worldwide (ca. 85 genera in New England and 55 in Vermont)

Ecology: Occur in practically all habitats, but specialize in dryer sites

Vegetative attributes: Perennial and sometimes annual herbs Upright stems (culms) round Nodes swollen Internodes hollow Leaves two-ranked, sheaths split Ligule often present

Reproductive attributes: Perianth, if present, of lodicules Androecium of usually 3 stamens Ovary superior, of 3 fused carpels Fruit a caryopsis

Floral Formula:

Florets are enclosed by two bracts, the palea and the lemma rachilla

Florets are arranged in spikelets, these subtended by a pair of glumes

‘Telescoped’ spikelet ‘Exploded’ spikelet of brome grass glumes ‘Telescoped’ spikelet ‘Exploded’ spikelet of brome grass

Inflorescences Various raceme panicle spike

Caryopsis (grain) Achene Loculicidal capsule Fruit Reduced to 2 (or 3) scales Absent or of bristles or scales Usually 6 chaffy tepals Perianth Spikelets Each flower subtended by 2 bracts (lemma and palea Each flower subtended by one bract (scale) Basically cymose and often congested Each flower subtended by 2 bracts Inflorescence 2-ranked Blades flat Open sheath 3-ranked Closed sheath Blades flat to terete Leaves Terete or ellipsoid Internodes hollow (to solid) Nodes jointed Triangular (not always visible) Internodes usually solid Nodes not jointed Terete in cross section Internodes solid with large pith Stems Various Wetlands and upland woods Mostly wet areas Habitat POACEAE (Grasses) CYPERACEAE (Sedges) JUNCACEAE (Rushes) Character

(First a couple of oddballs …) The major groups: (First a couple of oddballs …)

Spikelets enclosed in a spiny bur ... Cenchrus longispinus Field sandbur

Spikelets all unisexual, plants monoecious ... Zizania aquatica Wild rice

Glumes absent; spikelets strongly flattened ... Leersia oryzoides Rice cutgrass

Spikelets in two or more rows on one side of the rachis ... Magee and Ahles Group 1: Spikelets in two or more rows on one side of the rachis ... Spartina pectinata Freshwater cordgrass

Spikelets sessile on the rachis, forming a bilateral spike ... Magee and Ahles Group 2: Spikelets sessile on the rachis, forming a bilateral spike ... Elytrigia repens Quackgrass Lolium perenne Ryegrass

≥2 functional florets/spikelet; glumes shorter than lowest lemma ... Magee and Ahles Group 3: ≥2 functional florets/spikelet; glumes shorter than lowest lemma ... Bromus inermis Unarmed bromegrass Briza minor Smaller quakinggrass Eragrostis spectabilis Purple lovegrass

Magee and Ahles Group 4: ≥2 functional florets per spikelet; glumes longer than lowest lemma ... oat spikelet Danthonia spicata Poverty grass Avena sativa oats

Anthoxanthum odoratum Magee and Ahles Group 5: Functional floret 1/spikelet, this subtended by two sterile florets ... Phalaris arundinacea Reed canary grass Anthoxanthum odoratum Sweet vernal grass

Schizachyrium scoparium Magee and Ahles Group 6: Florets in pairs, one sessile and perfect, the other pedicelled and staminate ... Schizachyrium scoparium Little bluestem Sorghastrum nutans Indian grass

Magee and Ahles Group 7: Spikelets solitary, round in cross- section or dorsiventrally compressed ... Panicum sp. Panic grass Echinochloa sp. Barnyard grass

Spikelets solitary, laterally compressed ... Magee and Ahles Group 8: Spikelets solitary, laterally compressed ... Ammophila breviligulata Beachgrass Oryzopsis racemosa Black-seeded mountain ricegrass Millium effusum Millet